An optical assembly can be included in a head mounted display (HMD) in order to focus image light emitted from a display to an eye of a user that wears the HMD. However, layers of the optical assembly may generate Fresnel reflections. A portion of the Fresnel reflection may become incident on the eye of a user and noticeable to the user as ghost images. Ghost images may be distracting and otherwise bothersome to a user of an HMD.